This invention relates to a link rod connector and more particularly to a link rod connector for connecting a link rod at its one end to a link arm on the device to be operated and at its other end to a link arm on the member for operating the device so as to establish a mechanical connection for transmitting motion between the operating member and the device to be operated. The link rod connector according to this invention can be used, for example, in establishing a link for the transmission of motion between an automobile door lock mechanism and the outer or inner handle of the door.
Conventionally, the connection between a link arm and a link rod has been accomplished by bending the end of the link rod into the shape of the letter "L" and then using an L-shaped synthetic resin connector to connect the bent part of the link rod to the link arm in a manner which allows the link rod to rotate freely but not to be extracted from the connecting hole in the link arm. Another method that has been used entails the use of a synthetic resin connector having a nut portion. The connector is first rotatably attached to the link arm and then a threaded portion at the tip of the link rod is screw engaged with the nut portion of the connector.
In assembling link mechanisms of this type the procedure most commonly used is to first connect one end of the link rod to one or the other of the link arms for the operated device and the operating member and then to connect the other end of the link rod to the remaining link arm, whereafter the link arm is assembled into its associated device or member. Because of this, it is preferable to have a connector capable of retaining the link rod in connection with the link arm in a manner which allows the link rod to rotate with respect to the link arm but not to be extracted therefrom and, moreover, capable of permitting the link rod itself to rotate. In the conventional method first mentioned above, however, the only freedom of rotation allowed is between the link rod and the connector on the one hand and the link arm on the other, and no rotation of the link rod itself is possible. As a result, the work of assembling the link arms into their respective mechanisms is made complicated and it is impossible to adjust the effective linking length of the link rod. In the second mentioned method, the primary object is to permit adjustment of the effective linking length. Furthermore, as the link rod and the connector are rotatable with respect to the link arm and the link rod is itself also able to rotate, the work of assembling the link rod with the link arm is facilitated. However, with this method the effective length of the link rod is changed when the link arm is rotated about the axis of the link rod so that there is a danger that it may become impossible to obtain reliable transmission of the motion from the operating member to the operated device.